Method of making spiral coils



Feb. 19, 1924.` J. PRICE METHOD 0F MAKING SPIRAL ooILs Filed May 7. 19214 Sheets-Sheet 1 J; PRICE METHOD 0F MAKING SPIRAL cons Fs. 19, 1924.A

.Fileduay v; 1921 4 sheets-sheet 2 Fe.-Y '9,"'f9224.

v J.' PRICE METHOD QF MAKING SPIRAL coIL`s v 4 Sheets-sheet s Filed' Mayv. 1921 vwmttoz M, 12M, my( ,Wmaa

Feb. 19, 1924;'

J. PRICE METHOD OFIMA'KING SPIRAL COILS Filed' May 7. 1921 4Sheets-Sheet 4 @Mbembe/c MM -btommf l Wn Patented Feb. 19, 1924.

UNITI-:n STATESAVPATENT OFFICE.

JOSEPH PRICE, 0F NEW l YORK, N. Y., ASSIGNOR TOTHE GEISCOM RUSSELLCOMPANY,

0F NEW YOBK,'N. Y., A QORPORATION 0F DELAWARE.

lannion or'maxma srInAL coms.

` Application filed lay 7,

To all whom 'it may concern: v

.Be it known that I, J osnrH PRICE a citif zen of the United States,residing at lo. 203l West 11th Street, in the city and county of NewYork, State of New York, have invented certain new and usefulImprovements in Methods of Making Spiral Coils; and I do hereby declarethe following to be a full, clear, and ex'act description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.-

The present invention relates to method and apparatus for forming spiralcoils adapted vto be used in apparatusl for ex.- changing heat betweenfluids, particularly of coils of the general tyie disclosed in myco-pending app ication, filed February' 8, 1919. l

Heretofore coils of this type have been formed by winding ,av length ofstraight tubing into the desired spiral form, eginning at the center ofthe coil where the radius of the turns is small and winding onsuccessive turns until a coil of the desired diameter is produced. Informing double coils the winding must be begun approximately at themiddle of the tubin 'The portion from the middle to one en of the tubin-is wound into one fiat spiral coil and t e other half of the tubinginto another lat coil in parallelism with the first., a sufficientlength of tubing being left at the middle to constitutea continuous Huidpassage from one of the flat coil elements to the other. Sincesuccessive turns of the spiral enclose preceding turns it is impossibleto accomplish the winding of such a coil upon a spool or other type ofform block, and the winding has heretofore been accomplished by hand.

It is lthe prin-cipal object of the present invention to provide amethod for forming fiat spiral'coils of the above type which may becarried out/"conveniently and quickly and at low expense andv in whichfew hand operations are necessary. v

It -is also anv object of the vinvefntien to provide a method forformin' spiral coils 'which vmay be employed equal y well in themanufacture of double coil units in which the two elements areidentical, those inwhich the twov elements arel reversely wound, as well'as those'in which the corresponding turns of the two elements conerialNo. 275,746,

1921. Seal No. 467,658.

stituting the coilunit are sta gered relative .to the axisof the coil,which two lat#l In said rawings, 'Fi re 1 is a plan View showing' theman rel of the machine and its operating v mechanism;

Fig. vv2. is a vertical section through the centerline of the mandrel;

Fig. 3 is an end View looking from the ri ht of Figs. 1 and 2and showingalso the tu -support and guide;

Figs. 4 and 5 are diagrammatic views showing the movement of the tubeguide during the ceiling of the tube;

referred embodi- Yment of ap aratus there or.

Fig. v6 is a detail view of a portion of thc tube guide; n

Fig. 7 is an elevational view showing the coiled tube immediately afterit is removed vfrom the mandrel ;I i l Figs. 8 and 9 show in section andelevation, respectively, the completed coil:

Fig. 10 is an elevational view of the modied form of mandrel forproducing a different type of coil; Y

Fig. 11 is an elevational View showing the tube ready for coiling on themandrel Shown in Fig. 10;

Fig. 12 is an elevational view showin the modified coil as removed fromthe man rel; and

Figs. 13 and 14.- Show in section and elevation, respectively, thecompleted coil produced on the mandrel shown in Fig. 10.

Referring to Figs. 1 to 3 of the drawings,

1 indicates my vimproved mandrel which comprises two independentportions2 and 3 having the form of cone frustums with their smaller endsadjacent, thus lending the assembled mandrel a 'form similar to that ofan hour-glass. The cooperating portions 2 and 3 of the mandrel areattached to a v vvber 7 and which serves to support the shaft andmandrel for'rotation. The overhanging portion of the shaft is providedwith a .worin gear 9 fixed to the shaft and serving to rotate themandrel from a suitable power source, for instance, the individualelectric motor 10 and clutch 11 shown in the drawings.

The opposite 'end of the shaft 5 extends through the hub of the mandrelportion 2- shaft'so that it may be readily removed.- For this purposethere is provided a hand,

wheel 14 having an attached threaded collar 15 adapted to engage withthe threads 13 provided onl the end of the shaft 5. At the inner end ofthe threaded portion 15 is a ange 16 of diameter substantially equal tothe outer diameter of the hub of the mandrel portion. Bv screwingl upthe hand wheel 14 the mandrel portion y3 is firmly clamped between thefixed inner portion andthe fia-nge 16 yof the hand wheel. A plate 17which is diametrically split for the purpose of assembly may be fittedover the portion 15 and secured to the mandrel portion 3 by means of`-screws 18. This plate is adapted to engage against the outer face offlange 16' so that the mandrel portion will be positively drawn awayfrom the fixed mandrel portion by un`- screwing the hand wheel.

Thev outer mandrel portion 3 has a square counter-bore in its small endto tit over the end of the squared portion of the shaft whichprojectssomewhat beyond the small end of the mandrel art '2, thusassuring ythat the two parts of the mandrel will be fitted prop- Y erlytogetherand will be held against rela tive movement while the machine isin operation. The faces of the mandrel portions 2 land'3 are providedwith a groove 19 of form depending upon the particular type of coilvwhich it is desiredt'oproduce. For producing Spiral coils the groovebegins near the upper edge of the mandrel portion 2 and proceeds in aspiral v'course down the man` drel, the radius of its turns decreasingas it approaches the center of the mandrel, and assumesessentially theshape of a conical iral. The face of the mandrel portion 3 is anexactcomplement of the portion 2, and

l when placed end to end ,with the portion 2 a groove is formedextending continuously along the mandrel from end to end. lf desired, aspiral track Aor series of brackets arranged in spiral form may bepositioned upon the surface of themandrel forthe purpose of shaping thetubing into.' the desired form instead of employing a groove aslshown.

A clamping plate 20 is provided at the outer edge of the mandrel portion2 for holding in place the end of the tubing which isbeing formed into acoil. The plate` is secured in place by means of a bolt 21 and nutmesses 22. There is also provided at the outer edge of themandrel'portion 3 a handle 23 rigidly attached to the mandrel by meansof a screw 24. This handle is designed as a convenient means by which toproperly position the mandrel before the tubing is secured in place, andto furnish means by which the outer mandrel portion may be unscrewedfrom the coiled tube for dislodging the tubing from the groove 19 afterthe coil has been wound, so that the mandrel port-ion 2 may bewithdrawn. The free end of the mandrel may,` if desired, be supported ina fixed ring 40 provided With bearing rollers 41, to relieve the bearing6 of the overhung load tending to depress the mandrel during the coilingof the tube.

For the purpose of properly forming the coil tubing 1 on the mandrel, anindependent vertical supporting stand 25 carrying a ball joint 26 isprovided opposite the middle section of the mandrel and at some distancetherefrom. Plunger rod 27 is screwed at one end into the ball joint 26and extends from this joint to the mandrel. Rod 27 serves as asupporting core for the length of tubing 1 which is being formed into acoil, the tubing being first slipped over the supporting rod and thendrawn off by the rotation of the mandrel.

' The ball joint 26 lis mounted for pivotal movement in a verticaldirection and is also free to rotate about its vertical axis, thusgiving the working end of the plunger rod 27 freedom to move from end toend of the mandrel and also to follow the pitch of thevmandrel as thediameter of the turns varies. The ball joint is preferably placed at alevel somewhat above that of the mandrel axis for the purpose of causingthe end yof the plunger rod in following the surface of the mandrel tolie more nearly inI they vertical plane' passing through the axis of themandrel than would be the case if the ball joint were supported at thesame height as the mandrel shaft, in which case the end of plunger rod27 would describe roughly an, arc'each time it traveled from one endofthe mandrel to the other. A longitudinal passage is providedthroughout the length of the plunger rod and serves to deliver acoolingand lubricating fluid ito the tubing being formed. This Huid mav ofhandle 23. A straight length -of tubing l is then selected and slippedover the pluner rod 27. The end of the tubing adjacent t e mandrel isinserted beneath the clamp- 'as t e rotation proceeds. track on themandrel face serves as a guide ing plate `and 4the nut 22/tightened tosecure it firmly in place. The power source vis then .connected to the aparatus and the mandrel rotated at a re etermined s eed, the -length oftubing ing drawn o the plun er rod and wound upon the mandrel Thegrooved The chief purpose of the plunger rod is to prevent the tubecollapsingat the point l where it begins to bend and for that reason itis essential that the end of the rod move as closely as possible in thevertical plane of the axis of the mandrel, which is accomplished, asdescribed above, by su porting the outer end of the rod at t e properdistance above the axis of the mandrel. The relation of the rod to themandrel is graphically illustrated in Figs. 4 and 5. As shown in Fig. 4,the len of the rod is such that when pivoted in line with the middle ofthe mandrel, that is von line a-a,the end of the rod due to its movementin a horizontal plane as indicated by arc aa will intersect the plane ofthe axis of the mandrel at the large ends of the mandrel. As shown inFig. 5, the

height of the ball joint is so determined that the vertical movement ofthe end of the mandrel as indicated by arc b'- causes the end of themandrel to lie in the vertical plane of theaxis of the mandrel at thepoint of its smallest diameter. As the movement of theend of the rod isboth vertical and horizontal in followin the surface of the mandrel itsend face hes substantially at all times in the plane of the mandrelaxis.

The mandrel is kept in rotation until the entire groovel from the upperend of the mandrel portion 2 to the upper end of the mandrel portion 3,or any desired portion thereof, is filled, at which time the power isshut off and the apparatus brought to rest. The hand Wheel 14 is thenturned to unclamp the mandrel sections and by means of the .plate 17Vand iange 16 to shift the mandrel section 3 off the squared portion ofthe shaft 5. In this movement the part 2 will also be moved along thelshaft by the tube which is Wound around both mandrel parts, until thepartl 3 is entirely off l the squared portion of the shaft 5. The

hand wheel. 14 will preferably be screwed completely olf the end of 'theshaft so that the mandrel part 3 may be turned manually about thereduced round portion of the shaft 5 by means of handle 23 in adirection opposite to that in which groove 19 converges toward thecenter of the mandrel to lthereby unscrew the mandrel section 3 from thecoil tubing. When unscrewed sufliciently for the tubin to be clear ofthe spiral groove, the man rel ortion 3 may e completely removed. e

clamping plate 20 will then be unfastened to re ease theend of the .tubeand thus ermit the coil tubing to be unscrewed an removed from themandrel section 2.v The mandrel is now reassembled by returning theportion 2 in place on its shaft 5 in proper relation with the part 3 andscrewing up the hand wheel 14, after which another' coil may be formed.p

The character of the coiled tubing as it comes from the mandrel isillustrated in Fig. .7. The free ends 30 and 31 are at the outerextremities of the vconical portions and occur on the turns of lar estdiameter. To form a double fiat spiral coll, each of the conicalportions of the coil as it comes froln the mandrel is pressed into aflat coil by any convenient means, thus forming two closely adjacentparallel flat coils 35 and 36 as shown in Fig'. 8 and Fig. 9. `Since thegrooves on the two mandrel portions were so positioned as to cause theturns of one portion to be directly opposite the spaces between -turnson the other portion, the lturns of the vflat coils produced after thepressing oper ation lie in' staggered relation to the direction of theaxis of the coil. This featureis of value in apparatus for exchangingheat between iuids due to the fact that it causes the fluid to be filmedthrough the spaces formed between the staggered coil turns and insuresgood contact with the heat trans ferring surface. Thecoil ends 30 and 31are here shown extending out in parallelism at one side of the coil butmay be made f to assume other positions by cutting ofi' one of the coilends at a different length so that its opening will occur at a differentpoint on the periphery 'of the coil.`

`While the staggered relation of turns prevails throughout the greaterportion of the coil it will be observed from Fig. 9 that at twodiametrically opposite points 33 the adjacent turns of the` two fiatcoil portions cross each other, and at these points a 'free passage willoccur throughthe double coil unit in the direction lof the coil axis.Should successive coil units be positioned 4in a heat transferringapparatus in identical relation throughout the length of the apparatusthese open 'spaces would all fall in line, and there would be a tendencyfor some of the fluid passing through the apadapted for suchdisplacement by causing.

the inlet and outlet openings 30 and 31 to be positioned at differentportions of thel periphery in different coil units. For ex ample, theend 3() may be shortened somewhat and the end 31 may be lengthened anamount equal to that by which the end 30 is shortened, thus leavingI theinlet and outlet, openings vin the same position relative to each otherbut displaced la certain angular distance relative to the body of thecoil. j

This difference in the coils may readily be secured with the machineherein disclosed by merely changing the position of the clamping member20. For the purpose the fiange of the mandrel is provided with a seriesof holes in any one of which the bolt 2l may be set to give the clampingmember 20 a range of angular movement about the shaft 5 of aboutl 90, orany other desired amount. For the purpose of permitting the tube ends.of the completed unit the same relation to each other, the winding ofthe tubing is continued farther on the mandrel portion 3, this operationbeing accomplished with no appreciable change in the finished coil. In agiven heat exchange apparatus one half of the coils may be of the typeformed with the clamping member in its normal position and the otherhalf of the type formed with the clamping member 20 displaced 90. Whenthe coils are placed in the apparatus, alternate coils being of thedifi'erent types, a staggered relation will be secured and a free fluidpassage through the length of the shell will be eliminated. In Fig. 10 Ihave illustrated a mandrel adapted .to form double fiat spiral coilunits in' such manner as to avoid having a free passage for the fiuidthrough both coils of the unit' at any portion of the coil. The

mandrell is divided into two portions 2a and provided at' its face, thedirection of the` 3 which may be mounted for rotation in the manneralready described. Each of the portions 2 and 3 has afspiral groovegroove upon the portion 3a,being the reverse of that on the portion 12a.In the apparatus shown in Fig. 2 a continuous rotation in a clockwise'vdirection will cause the tube to follow the groove en ,to the end, whilein the mandrel shown in Fig. 10 the 'groove begins at the large end 'ofsection 2 and proceeds down to .the center of the meshes 2a arepositioned relative to those on thev portion 3a so that theyv lieopposite the spaces between grooves on the portion 3a..

In forming a. coil by means of this type Aof mandrel the length oftubing is first bent at lts middle to conform with the loop 34 formed bythe meeting grooves in the-two parts of the mandrel. The bent middleportion 34a of the tube is placed at the center of the mandrel 'Where itis clamped in fixed" position by means of a bolt with a wide head whichis screwed into the mandrel part 3a at'the beginning of its groove. Uponrotating the mandrelthe two halves of the tubing wind up simultaneouslyin the grooves on the mandrel portions 2a. and 3a, lforming two conicalspiral'coilsreversely wound and connected rby the.- middle bent portion.The two spiral portions of the coil are subsequently pressed fiat and afiat doubley coil unit -is formed, the turns of the elementsconstituting each' coil being `staggered relative to the axis of thecoil.

It is to be noted that the turns of the two fiat coil elementscomprising each unit lie in exact parallelism, they turns of one beingexactly opposite the spaces between turns of the other at all portionsof the unit, thus avoiding altogether points on the ...coil at which thespaces between turns of one come directly opposite the spaces :betweenturns of the other. This modification thus furnishes a completelystaggered path for the fiuid through the unit.v

In the type of construction. illustratedin Figs. 7 and 9 the workingfiuid passes com? pletely'through the coil unit from the inletpositioned at the periphery of one ofthe fiat coil elements to theoutlet positioned on the periphery of the other fiat coil element, thedirection of flow being the same throughout the coil. Thus the turns ofone coil proceed from the outer edge of the unit to' the inside,decreasing in radius, yand the turns of the other-'element increase inradius and proceed from. the inner to the outer portion of the coil,which feature necessitates a crossing of the turns of the two' fiat coilelements and the forming of points at which,v

the staggered `relation is not maintained. In the reversely wound coil,however, the

fiuid passes from the inlet atthe outer por-V .l

tion of one of the fiatcoil elements to theY inner turns, butat thecenter the flow is reversed and the iiuidpasses from the inner turns ofthe second fiat coil element to the outlet at the periphery of theelement in the A reverse direction.

While I have illustrated and described a preferred manner of carryingout my improved method of forming heat exchanging coils of the typedescribed and have illustrated a preferred embodiment of apparatustherefor, it is to be understood that the details of the method andparticular construction of the apparatus may be varied within the fullscope of the appended claims. For instance, the end of the mandrelfarthest from the bearing 6 may be supported by another bearing, insteadof being mounted to rest upon rollers in the manner shown. If themandrel is of unusual length a traveling carriage mounted for movementparallel to the mandrel axis may fbe employed in feeding the tubinginstead of the ball joint arrangement as shown. Also any desiredarrangement of clutch mechanism may be provided to eii'ect rotation ofthe mandrel.

I claim:

l. The method of forming flat spiral coils for heat exchanging apparatuscomprising winding the material of the coil into a conical spiral andsubsequently compressing the turns of said spiral into substantially thesame plane.

v2. The method of forming double flat spiral coil units for heatinterchange apparatus comprising winding' thematerial of the coil intotwo conical spirals and subsequently pressing the turns of each conicalspiral into substantially a single plane.

3. The method of forming double fiat spiral coil units for a heatexchange apparatus comprising winding the material of the coil into twoconical spirals having their small ends adjacent, the material of thecoil being continuous throughout the length of both spirals, andsubsequently compressing the turns of each spiral into substantially asingle plane.

4. The lmethod of forming double Hat spiral coil units for lieatexchange a paratus, comprising winding a straight tu ing into twoco-axial conical spirals and subsequently compressing the turns of eachspiral into substantially a single plane, the tubin forming a continuousiuid passage throug said spirals in series.

5. The method of forming double flat spiral coil units for heat exchangeapparatus, comprising forming the material of the coil into tworeversely Wound conical spirals having their smaller ends adjacent, theturns of one of said spirals being opposite the spaces between turns ofthe other.

6. The method of forming double flat spiral coil units for heat exchangeapparatus, comprising winding the material of the coil into two conicalspirals and subsequently compressing the turns of each spiral intosubstantially a flat coil, said Hat coils lyin closely adjacent and theturns of each of sai coils being directly opposite the intersticesbetween turns of the other.

7. The method of forming double fiat spiral coil units for heat exchangeapparatus,

comprising winding up a length of tubing into a conical spiral form,then reversing the direction of the tubing, then winding up anotherconical spiral in a direction reversed from that of said first spiraland subsequently attening the respective conical coils into a doubleflat spiral coil.

8. The method of forming double flat spiral coil units for heat exchan eapparatus, comprising winding up a lengt of straight tubing into a coilof a conical spiral conformation beginning at the larger end and workingtoward the apex of the cone, then reversin the direction of the tube atthe apex an winding up a second coil of conical spiralv conformationbeginning at the apex and proceeding toward the base, the turns of saidsecond coll lying opposite the interstices between turns of said firstcoil, and then suitably ilattening said respective coils to form adouble flat spiral coil unit.

In testimony whereof I affix my signature.

JOSEPH PRICE.

